Costs associated with operating a web-based product service can increase significantly as users are added to the service. Such costs can include bandwidth, electricity, and facilities. One key component of many product services is the updating of files associated with a product or service, in order to maintain the highest quality experience possible for the users. Update services typically provide an online service from which the latest files for associated products and services can be downloaded. Reducing the cost of distributing update files would benefit many such services.